Mobile robotic devices are useful in a variety of civilian, military, and law enforcement applications. For instance, a robotically controlled mobility platform can inspect or search buildings with structural damage caused by earthquakes, floods, or hurricanes, or can inspect buildings or outdoor sites contaminated with radiation, biological agents such as viruses or bacteria, or chemical spills. The platform can carry appropriate sensor systems for its inspection or search tasks. Military and law enforcement applications include operations that are deemed too dangerous for soldiers or law enforcement officers. For instance, the robot can be used to leverage the effectiveness of a human “pointman,” and may also be used for reconnaissance, surveillance, bomb disposal and security patrols.
The use of robotic devices for bomb, artillery shell, and mine disposal purposes is of particular importance in military and law enforcement fields, where the use of a robotic device in an area seeded with mines or improvised explosive devices (IEDs) can greatly reduce the danger to human life. In these applications, a robotic device, controlled by an operator located a safe distance from the danger, or programmed to function autonomously, can be used to search for and disarm explosive devices that would otherwise require a human to locate and disarm manually.
One particular function of these robotic devices is to safely lift and transport explosive devices, such as the artillery shells often used in IEDs, to either remove them from a dangerous location or disarm them safely. These IEDs can be located above ground or imbedded within the ground, and can use a number of explosive devices. One such explosive device often used in IEDs is a 155 mm artillery shell, the weight of which may be about 96 lbs.
The existing state of the art requires large and heavy robots in order to lift and carry explosives such as mortar, artillery, and tank shells. Typically, the robot will need to be at least three to four times the weight of the ordnance it can lift and carry, according to conventional methods. These large and heavy robots may be limited in operational effectiveness, by, for example, being unable to enter small spaces, or travel over fragile or structurally damaged surfaces and floors. Large and heavy robots are also more difficult to transport and deploy, limiting the locations and situations in which such robotic devices can be utilized.
Smaller robotic devices are available for use in military and law enforcement applications, but have difficulty lifting and transporting larger and heavier objects, while still maintaining full operational functionality. One such robotic device is disclosed in U.S. Pat. No. 6,263,989, the disclosure of which is incorporated herein by reference in its entirety. A commercially available version of the robotic device described in the patent is available from iRobot Corporation, Burlington, Mass. under the trade name PackBot® robot.
From the foregoing, there is a need for a method and apparatus to allow smaller and lighter robotic devices, such as the PackBot® robot, to lift and transport ordnance that actually weigh significantly more than the robot itself. The addition of an apparatus for lifting and transporting heavy ordnance to lighter robotic devices will greatly increase the operational range and flexibility of robots in bomb disposal and other associated missions, allowing for the safe disposal of IEDs and other explosive devices in a wider variety of locations and conditions, and thus greatly reducing the risk to human life.